This invention relates generally to multi-functional apparatuses and specifically to a multi-functional apparatus employing a linear motor for use in an automotive vehicle.
Almost all automotive vehicles have a single or a pair of windshield wiper assemblies. These assemblies traditionally include rubber wiper blades mounted upon claw brackets. These claw brackets are attached to wiper arms mounted upon rotating shafts. These shafts are either directly driven by electric motors or driven by a single electric motor which actuates series or parallel-coupled four-bar linkage mechanisms. It is further known to provide a wiper system in combination with a wash device, to clean headlamps for automotive vehicles.
It is also common to employ a window wiper assembly for cleaning rear windows of automotive vehicles. Typically, these types of rear window wiper assemblies include a wiper blade mounted upon a bracket which is coupled to a wiper arm. The wiper arm is attached to a wiper shaft rotatably driven in a cyclical oscillating manner by a helical gear. A reversible, fractional horsepower, dc electric motor serves to actuate the helical gear through an armature shaft-mounted worm gear enmeshed therewith. This type of rear window wiper arrangement is usually mounted upon a pivoting liftgate of a minivan, station wagon, sport-utility vehicle or the like. Examples of conventional window wiper assemblies and motor mechanisms are disclosed within the following U.S. Patents: U.S. Pat. No. 4,893,039 entitled "Windshield Wiper Motor" which issued to Isii on Jan. 9, 1990; U.S. Pat. No. 4,878,398 entitled "Driving Device for Window Wiper of Motor Vehicles" which issued to Heinrich on Nov. 7, 1989; U.S. Pat. No. 4,336,482 entitled "Rear Window Wiper Motor Control" which issued to Goertler et al. on Jun. 22, 1982; U.S. Pat. No. 4,259,624 entitled "Arrangement for Wiping a Vehicle Window" which issued to Seibicke on Mar. 31, 1981; U.S. Pat. No. 3,694,723 entitled "Motor Vehicle Windshield Wiper Having a Parking Position Outside the Wiper Area" which issued to Schneider et al. on Sep. 26, 1972; and, U.S. Pat. No. 3,665,772 entitled "Windshield Wiper Motor Link Depressed Park Mechanism" which issued to Beard et al. on May 30, 1972. All of these patents are incorporated by reference herewithin.
Recently, linear-motion wiper structures have been proposed as an alternative to conventional arcuate-motion wiper structures. One such structure comprises a multi-stage hydraulic cylinder arm which can be driven by a transmission mechanism having both vertical and horizontal displacement functionality whereby a blade, which is driven by the arm, can wipe on the windshield in a linear reciprocating motion so as to completely clear the drops of rain on the windshield, and this may provide a clear vision for users who drive in the rain. An example of this structure is disclosed in U.S. Pat. No. 4,782,548 which issued to Wong on Nov. 8, 1988, the entire disclosure of which is hereby incorporated by reference.
Additionally, an alternative linear-motion wiper structure has been proposed. This apparatus for wiping a window has a wiper, a first track substantially parallel to at least a portion of the window and a second track substantially parallel to and displaced from the first track. A first motorized drive wheel is provided for driving the wiper along the first track in a first direction and a second motorized drive wheel for driving the wiper along the second track in a second direction, opposite to the first direction, so as to wipe the window. The wiper is preferably designed to reduce drag-back of water across the window. In a preferred embodiment, curved connecting tracks connect between the ends of the first track and the second track so as to form a closed loop track. A single motorized drive wheel is used. The single motorized drive wheel may be driven by a motor rotatably associated with the wiper, or through a flexible drive cable by a remotely mounted motor. Other embodiments use a single substantially linear track in combination with a motor running unidirectionally. An example of this structure is disclosed in U.S. Pat. No. 5,564,156 which issued to Habba on Oct. 15, 1996, the entire disclosure of which is hereby incorporated by reference.
Some conventional vehicles also provide a rear window release lock or latch, actuated by a solenoid, which can be unlocked to allow for upward pivotal movement of the rear window in relation to the otherwise stationary liftgate. In combination therewith, a separate liftgate lock is often mounted upon the liftgate door for fastening the liftgate to the body to prevent inadvertent pivotal opening.
This liftgate lock is traditionally operated by manual key or handle rotation, or through a separate electric motor or solenoid.
Additionally, separate motors and solenoids are required to actuate passenger door locks, an antenna retraction mechanism, headlamp cover retraction mechanisms, a fuel filler door lock and other similar functions. The traditional need for such a multiplicity of electromagnetic devices has increased the automotive vehicle weight and cost while further proving difficult to package within the often small spaces provided. This added weight is especially detrimental when the window wiper mechanism, rear window lock and liftgate lock, as well as their distinct respective electromagnetic devices, are all incorporated within the pivoting liftgate. Not only is the piece cost increased due to this multiplicity of electromagnetic devices, but the assembly cost, part number proliferation and handling costs, electrical wiring costs, objectional motor noise, and failure modes are increased.
Recently, a multi-functional apparatus employing an intermittent motion mechanism has been proposed. A single electromagnetic device selectively causes movement of the intermittent motion mechanisms thereby moving mechanical devices coupled thereto. In a specific embodiment, the armature shaft of an electric motor rotates a worm gear segment which then drives a helical gear mounted in a gear housing. Via a series of pins, cams and gears, also mounted in the housing, this input can be made to drive selectively two or three intermittent rotary motion mechanisms according to the rotary position of the helical gear. Mechanical devices which are coupled to the intermittent rotary motion mechanisms, e.g., a rear window wiper, a liftgate lock and a liftgate window release lock, are therefore operated according to the positional range of oscillation or movement of the helical gear. In this way, the number of electromagnetic devices, or motors, required to be fitted to a vehicle liftgate is reduced. An example of this apparatus is disclosed in U.S. patent application Ser. No. 08/430,388 to Zimmer et al. which was filed on Apr. 28, 1995, the entire disclosure of which is hereby incorporated by reference.
Additionally, a multi-functional apparatus employing an electromagnetic device has been proposed. To save weight and space and reduce costs in a vehicle, a multi-functional apparatus is used in place of a plurality of single-function devices. The multi-functional apparatus employs a single electromagnetic device to selectively actuate a plurality of intermittent motion mechanisms, thereby operating mechanical devices attached thereto. In a specific example, a reversible dc electric motor selectively drives a rear window wiper via a transmission, a clutch and a driven shaft. By rotating the transmission member beyond the rotational range for operating the wiper, drive to the wiper is disengaged and a locking mechanism for the rear window or liftgate can also be actuated by the rotating transmission member. In another aspect, a single electric motor selectively actuates three intermittent motion mechanisms thereby causing three mechanical devices coupled thereto to operate (e.g., rear window and liftgate locking mechanisms and a window wiper). An example of this apparatus is disclosed in U.S. patent application Ser. No. 08/431,148 to Maue et al. which was filed on Apr. 28, 1995, the entire disclosure of which is hereby incorporated by reference.
Finally, a control system for an automotive vehicle multi-functional apparatus has been proposed. A control system for an automotive vehicle multi-functional apparatus employs an electronic control unit operably controlling a rear window wiper assembly. In another aspect, an electronic control unit is operable as a multiplexed rear node for controlling a variety of liftgate devices and functions. In a further aspect, an electronic control unit controls a single multi-functional electromagnetic device. The multi-functional electromagnetic device uses intermittent motion mechanisms to selectively operate differing devices driven therefrom. A method of operating the electronic control unit is also provided. An example of this system is disclosed in U.S. patent application Ser. No. 08/431,149 which was filed on Apr. 28, 1995, the entire disclosure of which is hereby incorporated by reference.